In the field of telecommunications, a communications protocol is the set of standard rules for data representation, signaling, authentication and error detection required to send information over a communications channel. Communication protocols for digital computer network communication have features intended to ensure reliable interchange of data over an imperfect communication channel.
The Internet and Internet Communication Protocols
The Internet is a global network of interconnected computers, enabling users to share information along multiple channels. Typically, a computer that connects to the Internet can access information from a vast array of available servers and other computers by moving information from them to the computer's local memory. The same connection allows that computer to send information to servers on the network; that information is in turn accessed and potentially modified by a variety of other interconnected computers. A majority of widely accessible information on the Internet consists of inter-linked hypertext documents and other resources of the World Wide Web (WWW). Computer users typically manage sent and received information with web browsers; other software for users' interface with computer networks includes specialized programs for electronic mail, online chat, file transfer and file sharing.
The Internet Protocol (IP) is a protocol used for communicating data across a packet-switched internetwork using the Internet Protocol Suite, also referred to as TCP/IP. The movement of information in the Internet is achieved via a system of interconnected computer networks that share data by packet switching using the standardized Internet Protocol Suite (TCP/IP). It is a “network of networks” that consists of millions of private and public, academic, business, and government networks of local to global scope that are linked by copper wires, fiber-optic cables, wireless connections, and other technologies.
IP is the primary protocol in the Internet Layer of the Internet Protocol Suite and has the task of delivering distinguished protocol datagrams (packets) from the source host to the destination host solely based on their addresses. For this purpose the Internet Protocol defines addressing methods and structures for datagram encapsulation. The first major version of addressing structure, now referred to as Internet Protocol Version 4 (IPv4) is still the dominant protocol of the Internet, although the successor, Internet Protocol Version 6 (IPv6) is being actively deployed worldwide.
Data from an upper layer protocol is encapsulated as packets/datagrams (the terms are basically synonymous in IP). Circuit setup is not needed before a host may send packets to another host that it has previously not communicated with (a characteristic of packet-switched networks), thus IP is a connectionless protocol. This is in contrast to Public Switched Telephone Networks that require the setup of a circuit before a phone call may go through (connection-oriented protocol).
An Internet Protocol (IP) address is a numerical identification (logical address) that is assigned to devices participating in a computer network utilizing the Internet Protocol for communication between its nodes. Although IP addresses are stored as binary numbers, they are usually displayed in human-readable notations, such as 208.77.188.166 (for IPv4), and 2001:db8:0:1234:0:567:1:1 (for IPv6).
Cellular Networks and Cellular Network Communication Protocols
A cellular network is a radio network made up of a number of radio cells (or just cells) each served by a fixed transmitter, known as a cell site or base station. These cells are used to cover different areas in order to provide radio coverage over a wider area than the area of one cell. Cellular networks are inherently asymmetric with a set of fixed main transceivers each serving a cell and a set of distributed (generally, but not always, mobile) transceivers which provide services to the network's users
The most common example of a cellular network is a mobile phone (cell phone) network. A mobile phone is a portable telephone which receives or makes calls through a cell site (base station), or transmitting tower. Radio waves are used to transfer signals to and from the cell phone. Large geographic areas (representing the coverage range of a service provider) are split up into smaller cells to deal with line-of-sight signal loss and the large number of active phones in an area. In cities, each cell site has a range of up to approximately ½ mile, while in rural areas the range is approximately 5 miles. In clear open areas, a user may receive signal from a cell site 25 miles away. Each cell overlaps other cell sites. All of the cell sites are connected to cellular telephone exchanges “switches”, which in turn connect to the public telephone network or another switch of the cellular company.
As a phone user moves from one cell area to another, the switch automatically commands the handset and a cell site with a stronger signal (reported by the handset) to go to a new radio channel (frequency). When the handset responds through the new cell site, the exchange switches the connection to the new cell site.
A “GSM network” is a global system for a mobile communications network that generally includes the following functional parts:
MSC—the mobile service switching centre (MSC) is the core switching entity in the network. The MSC is connected to the radio access network (RAN); the RAN is formed by the base station controllers and one or more base transceiver stations (BSCs and BTSs) within a Public Land Mobile Network (PLMN). Users of the GSM network are registered with an MSC; all calls to and from the user are controlled by the MSC. A GSM network has one or more MSCs, geographically distributed.
VLR—the visitor location register (VLR) contains subscriber data for subscribers registered in an MSC. Every MSC contains a VLR. Although the MSC and VLR are individually addressable, in general, they are usually both contained in one integrated node.
GMSC—the gateway MSC (GMSC) is the switching entity that controls mobile terminating calls. When a call is established towards a GSM user/subscriber, a GMSC contacts the HLR of that subscriber, to obtain the address of the MSC where that subscriber is currently registered. That MSC address is used to route the call to that subscriber.
HLR—the home location register (HLR) is the database that contains a subscription record for each subscriber of the network. A GSM subscriber is normally associated with one particular HLR. The HLR is responsible for the sending of subscription data to the VLR (during registration) or GMSC (during mobile terminating call handling).
CN—the core network (CN) consists of, among other things, the MSC(s), GMSC(s) and HLR(s). These entities are the main components for call handling and subscriber management. Other main entities in the CN are the equipment identification register (EIR) and authentication centre (AUC); and
BSS—the base station system (BSS) is composed of one or more base station controllers (BSC) and one or more base transceiver stations (BTS). The BTS contains one or more transceivers (TRX). The TRX is responsible for radio signal transmission and reception.
A “mobile originated call” is a call in which the MSC that is handling the call is the serving MSC for the call and the calling user/subscriber is the served subscriber. Similarly, a “mobile terminated call” means the GMSC that is handling the call is the serving GMSC for the call and the called subscriber is the served subscriber.
Modern mobile phones use cells because radio frequencies are a limited, shared resource. Cell-sites and handsets change frequency under computer control and use low power transmitters so that a limited number of radio frequencies can be reused by many callers with less interference. Since almost all mobile phones use cellular technology, including GSM, CDMA, and AMPS (analog), the term “cell phone” is used interchangeably with “mobile phone”; however, an exception of mobile phones not using cellular technology is satellite phones.
Short Message Service (SMS) and SMS Protocols
Short Message Service (SMS) is a communication service standardized in the GSM mobile communication system, using standardized communications protocols allowing the interchange of short text messages between mobile telephone devices. SMS text messaging is the most widely used data application on the planet, with 2.4 billion active users, and most of all mobile phone subscribers sending and receiving text messages on their phones. The SMS technology has facilitated the development and growth of text messaging. The connection between the phenomenon of text messaging and the underlying technology is so great that in parts of the world the term “SMS” is used as a synonym for a text message or the act of sending a text message, even when a different protocol is being used.
SMS as used on modern handsets was originally defined as part of the GSM series of standards in 1985 as a means of sending messages of up to 160 characters (including spaces), to and from GSM mobile handsets. Since then, support for the service has expanded to include alternative mobile standards such as ANSI CDMA networks and Digital AMPS, as well as satellite and landline networks. Most SMS messages are mobile-to-mobile text messages, though the standard supports other types of broadcast messaging as well.
The Short Message Peer-to-Peer (SMPP) protocol is a telecommunications industry protocol for exchanging SMS messages between SMS peer entities such as short message service centers. It is often used to allow third parties (e.g. value-added service providers like news organizations) to submit messages, often in bulk. The protocol is based on pairs of request/response PDUs (protocol data units, or packets) exchanged over OSI layer 4 (TCP session or X.25 SVC3) connections. PDUs are binary encoded for efficiency.
The most commonly used versions of SMPP are v3.3, the most widely supported standard, and v3.4, which adds transceiver support (single connections that can send and receive messages). Data exchange may be synchronous, where each peer must wait for a response for each PDU being sent, and asynchronous, where multiple requests can be issued in one sending and acknowledged in a skew order by the other peer. The latest version of SMPP is v5.0.
The Secure SMS Messaging Protocol (SSMS) was initially invented to enhance the security of SMS messages sent by the GSM network. The Global Service for Mobile communications (GSM) with the greatest worldwide number of users succumbs to several security vulnerabilities. In the GSM, only the airway traffic between the Mobile Station (MS) and the Base Transceiver Station (BTS) is optionally encrypted with a weak and broken stream cipher.
SSMS is a new secure application layer protocol that efficiently provides the desired security attributes for the SMS messages to be used as a secure bearer in payment systems. SSMS efficiently provides the confidentiality, integrity, authentication, and non-repudiation for the SMS messages. It makes the SMS messaging suitable for the mobile payment and mobile commerce applications where the security is the great concern.
Signaling System 7 (SS7)
Signaling System Number 7 (SS7) is a set of telephony signaling protocols which are used to set up most of the world's public switched telephone network telephone calls. The main purpose is to set up and tear down telephone calls. Other uses include number translation, prepaid billing mechanisms, short message service (SMS), and a variety of other mass market services.
It is usually abbreviated as Signaling System No. 7, Signaling System #7, or just SS7. In North America it is often referred to as CCSS7, an acronym for “Common Channel Signaling System 7”. In some European countries, specifically the United Kingdom, it is sometimes called C7 (CCITT number 7) and is also known as number 7 and CCIS7. (ITU-T was formerly known as CCITT.)
There is only one international SS7 protocol defined by ITU-T in its Q.700-series recommendations. There are however, many national variants of the SS7 protocols. Most national variants are based on two widely deployed national variants as standardized by ANSI and ETSI, which are in turn based on the international protocol defined by ITU-T. Each national variant has its own unique characteristics. Some national variants with rather striking characteristics are the China (PRC) and Japan (TTC) national variants.
The Internet Engineering Task Force (IETF) has also defined level 2, 3, and 4 protocols that are compatible with SS7 MTP2 (M2UA and M2PA) MTP3 (M3UA) and SCCP (SUA), but use an SCTP transport mechanism. This suite of protocols is called SIGTRAN.
SMS Message Size
Transmission of short messages between the SMSC and the handset is done using the Mobile Application Part (MAP) of the SS7 protocol. Messages are sent with the MAP mo- and mt-ForwardSM operations, whose payload length is limited by the constraints of the signalling protocol to precisely 140 octets (140 octets=140*8 bits=1120 bits). Short messages can be encoded using a variety of alphabets: the default GSM 7-bit alphabet (shown above), the 8-bit data alphabet, and the 16-bit UTF-16/UCS-2 alphabet. Depending on which alphabet the subscriber has configured in the handset, this leads to the maximum individual Short Message sizes of 160 7-bit characters, 140 8-bit characters, or 70 16-bit characters (including spaces).
SMS Gateway and SMS Gateway Providers
SMS gateway is the term used to describe a service transforming messages to mobile network traffic from other media, or vice versa, allowing transmission or receipt of SMS messages without the use of a mobile phone. Typical use of a gateway would be to forward simple e-mail to a mobile phone recipient.
SMS gateway providers facilitate the SMS traffic between businesses and mobile subscribers, being mainly responsible for carrying mission-critical messages, SMS for enterprises, content delivery and entertainment services involving SMS, e.g. TV voting. Considering SMS messaging performance and cost, as well as the level of messaging services, SMS gateway providers can be classified as aggregators or SS7 providers.
The aggregator model is based on multiple agreements with mobile carriers to exchange 2-way SMS traffic into and out of the operator's Short Message Service Centre (SMS-C), also known as ‘local termination model. Aggregators lack direct access into the SS7 protocol, which is the protocol where the SMS messages are exchanged. These providers have no visibility and control over the message delivery, being unable to offer delivery guarantees. SMS messages are delivered in the operator's SMS-C, but not the subscriber's handset.
Another type of SMS gateway provider is based on SS7 connectivity to route SMS messages, also known as international termination model. The advantage of this model is the ability to route data directly through SS7, which gives the provider total control and visibility of the complete path during the SMS routing. This means SMS messages can be sent directly to and from recipients without having to go through the SMS-C of other mobile operators. Therefore, it's possible to avoid delays and message losses, offering full delivery guarantees of messages and optimized routing.
SMS Interconnectivity with Other Networks
Message Service Centers communicate with the Public Land Mobile Network (PLMN) or PSTN via Interworking and Gateway MSCs. Subscriber-originated messages are transported from a handset to a Service Centre, and may be destined for mobile users, subscribers on a fixed network, or Value-Added Service Providers (VASPs), also known as application-terminated. Subscriber-terminated messages are transported from the Service Centre to the destination handset, and may originate from mobile users, from fixed network subscribers, or from other sources such as VASPs.
It is also possible, on some carriers, for non-subscribers to send messages to a subscriber's phone using E-Mail. For example an AT&T subscriber whose phone number was 555-555-5555 would receive e-mails to 5555555555@txt.att.net as text messages. Sending a message this way is free but subject to the normal length limit.
Short messages can also be used to send binary content such as ringtones or logos, as well as Over-the-air programming (OTA) or configuration data. Such uses are a vendor-specific extension of the GSM specification and there are multiple competing standards. An alternative way for sending such binary content is EMS messaging which is standardized and not dependent on vendors.
Today, SMS is also used for M2M (Machine to Machine) communication. For instance, there is an LED display machine controlled by SMS, and some vehicle tracking companies use SMS for their data transport or telemetry needs. SMS usage for these purposes are slowly being superseded by GPRS services due to their lower overall costs.
SMS was originally designed as part of GSM, but is now available on a wide range of networks, including 3G networks. Commercially SMS is a massive industry in 2006 worth over 81 billion dollars globally.
SMS and IP
IP is not generally used within cellular operators' networks to carry traditional SMS; this is accomplished using SS7. However, IP is often used to carry the short message data external to the cellular network. Examples of such usage include messages submitted to a message processor from an originating machine using a web-based (HTTP over TCP over IP), an email (SMTP over TCP over IP) or a paging (SMPP over TCP over IP) interface.
Short Code
Short codes, also known as short numbers, are special telephone numbers, significantly shorter than full telephone numbers, which can also be used to address SMS and MMS messages from mobile phones or fixed phones.
They are designed to be shorter to read out and easier to remember than normal telephone numbers. While similar to telephone numbers, they are, at the technological level, unique to each operator, although providers generally have agreements to avoid overlaps. In some countries, such as the United States, some classes of numbers are inter-operator (U.S. inter-operator numbers are called Common Short Codes).
Short codes are widely used for value-added services such as television voting, ordering ringtones, charity donations and mobile services. Messages sent to short code can be billed at a higher rate than a standard SMS.
Normal telephone numbers (following the E.164 standard) form a prefix code: no numeral used as a telephone number acts simultaneously as the prefix of another, since conventional land-line phones have no mechanism to say “this is the end of the number”. On mobile phones, numbers are sent all at once, so the network knows the end of the dialed number, and thus one can use short numbers without clashing with longer numbers. For instance, on a land-line phone, one could not use the short code 12345, since then one could not dial the phone number 1 234 567 8901 (or 1 234 500 0000, or any other number that shared the prefix 12345), but on a mobile phone there is no such ambiguity.
Short codes are often associated with automated services. An automated program can handle the response and typically requires the sender to start the message with a command word or prefix. The service then responds to the command appropriately. In ads or in other printed material where a provider has to inform about both the prefix and the short code number, the advertisement will typically follow this format:
Example 1—Long version: Text Football to 72404 for latest football news.
Example 2—Short version: football@72404
Premium-Rated Short Messages
Short messages may be used to provide premium rate services to subscribers of a telephone network. Mobile terminated short messages can be used to deliver digital content such as news alerts, financial information, logos and ring tones. The Value-added service provider (VASP) providing the content submits the message to the mobile operator's SMSC(s) using a TCP/IP protocol such as the short message peer-to-peer protocol (SMPP) or the External Machine Interface (EMI). The SMSC delivers the text using the normal Mobile Terminated delivery procedure. The subscribers are charged extra for receiving this premium content, and the amount is typically divided between the mobile network operator and the VASP either through revenue share or a fixed transport fee.
Mobile originated short messages may also be used in a premium-rated manner for services such as televoting. In this case, the VASP providing the service obtains a Short Code from the telephone network operator, and subscribers send texts to that number. The payouts to the carriers vary by carrier and the percentages paid are greatest on the lowest priced premium SMS services. The submission of the text to the SMSC is identical to a standard MO Short Message submission, but once the text is at the SMSC, the Service Centre identifies the Short Code as a premium service. The SC will then direct the content of the text message to the VASP, typically using an IP protocol such as SMPP or EMI. Subscribers are charged a premium for the sending of such messages, with the revenue typically shared between the network operator and the VASP. Limitations of short codes include the limitation to national borders (short codes have to be activated in each country where the campaign takes place), as well as being expensive to sign up together with mobile operators.
An alternative to inbound SMS is based on Long numbers (international number format, e.g. +44 7624 805000), which can be used in place of short codes for SMS reception in several applications, such as TV voting, product promotions and campaigns. Long numbers are internationally available, as well as enabling businesses to have their own number, rather than short codes which are usually shared across a lot of brands. Additionally, Long numbers are non-premium inbound numbers.
Distribution of Goods and Services
Goods and services are widely available over the various global communications networks, including the internet and GSM networks. However, purchasing goods and services on such networks, such as for example the internet, often requires a preliminary internet search to locate a website providing a specific good or service desired by a user. In addition, after an appropriate website is located, the user must then also provide additional and detailed data to the website relating to (1) the user's identity, (2) billing information of a third-party relating to the user's source for purchase credit, and (3) user chosen delivery options. These data input tasks can be particularly challenging to a mobile user having a small form-factor mobile device, and especially due to the limited viewing access on the device for viewing the webpage and the smaller key-pad for providing data input through the device.
Within the telecommunications industry, and in particular with respect to the major wireless service providers in that industry, select goods or services can be associated with a numeric code known as a Common Short Code (CSC), or simply a “short code”, for access by a mobile user. Industry standard implementations of these CSC numbers are limited in that the CSC is merely used as a numeric code used for address identification and contains no other intrinsic function. Wireless service providers have deployed CSC short codes, which are phone numbers that are input via Short Message Service (SMS) text messages and forwarded by a user to the provider. Then the associated goods or services are ordered and billed for using the provider's billing systems.
In order for a distributor to obtain a CSC number for that distributor to associate with a good or service, the distributor must first lease or otherwise obtain a CSC number from a CSC trade association. Then the distributor must negotiate with each wireless service provider to support the leased CSC number. CSC numbers are unique within a domestic wireless service provider network system and only operate within an approving provider's network. When a distributor implements a CSC number this way, the distributor cannot use the CSC number internationally and the CSC number will have other cross-network limitations. Additionally, CSC numbers implemented this way through a wireless service provider's network do not operate through internet communication protocols for web-based applications.
The present invention is not in any way limited to just distributing a good or service associated with a Common Short Code (CSC). However, the systems and methods of the present invention provide for an alternate channel to distribute any good or service associated with a CSC, but without the typical difficulties associated with conventional CSC distribution channels, such as international boundaries or cross-network limitations. According to the present invention, these same goods and services can still be distributed through the domestic wireless service provider network systems in which a CSC has been approved. However, any regional, national or international communications network can be used in distributing the same goods and services.